[lammps-users] Group force

Dear all,

I want to do a indent simulation with the aid of LAMMPS, there are a specimen and a indenter in the simulation. And I want to obtain the indenter’s y-direction force, as normal force. The command “compute 1 indenter reduced fy” is adopted to obtain the normal force. However, the force-displacement curve obtained is not agree with my expection, which is shown is attached Figure 1. From some papers published about the indentation process, the force-displacement curve should has the similar trend of the attached Figure 2. So I really don’t know what’s wrong with the force date obtained. Will anybody give me some advice?

Best ragards


Figure 2.jpg

Figure 1.jpg

How are you doing the indentation? Is there something forcing
the indenter into the surface? Are you subtracting out that force?